I recently restarted my laptop. I had just finished uninstalling microsoft office. When it started booting back up, I got to the log in screen only to have it start flickering every 15 seconds or so. There is no image or anywhere to type my password anywhere, only the background. And when I try to restart it, the secondary keyboard I attached to it doesn't work, because I can't select safe mode, it kind of freeze lags movement. So I was able to launch in safe mode by hitting f8, but I still can't log in and it still flickers. When I plug in another keyboard at the same time, I can use the secondary one attached just fine. I spilt some liquid 2 months ago on my keyboard, and it doesn't work. So i use a secondary one, but the laptop never had problems. I have a lot of files on there I've been working on for the past few days that I haven't backed up yet on my external. As long as I can do that, if I can't figure out a solution, I'd want to reinstall the operating system. But I need that back up. Thank you whoever responds.
HP Probook 4540s
Windows 7 professional 64-bit